Process for centrifugal separation



Patented Sept. 9, :1930 I UNITED STATES PATENT OFFICE JULIEN IBERGI L QF TIRLEMONT, BELGIUM, ASSIGNOB TO THE FIRM RAFFINERIE TIE-La.

MONTOISE SOGIETE ANONYME, OF TIRLEMONT, BELGIUM Y PROCESS FOR CENTR-IFUGAL SEPARATION liquid. The crystals were in a moist condition owing to someportion of the mother liquor still adhering to them and had, consequently, to be exposed to a subsequent drying process. Also, the adhering mother liquor rendered the crystals impure, particularly in the case of sugar massecuite, so

that a washing process was necessary in order to remove the impurity due to the adhering liquor, a washing fluid such as steam or water being applied to the crystals remaining in the centrifugal drum. In this process, however, the superficial portions of the crystals were dissolved by the cleansing fluid and the yield of crystals diminished. Also, the

crystals left the centrifuge still in a moist condition and a subsequent drying process was required,

The object of the invention is to obviate.

both the subsequent drying 'and' also the washing of the crystals together with the consequent loss in yield, by increasing the centrifugal force by raising the speed of rotation of the centrifuge to an extent such that the surface adherence of the mother liquor to the crystals whichis known to involve phenomena other than that of capillary attraction in the interstices formed between the sugar crystals and that of surface tension is overcome andthe liquor is driven entirely or almost entirely from the crystals. In the same way crystals, which are still moist or impure, and which have been previously separated from the mother liquor, such as raw sugar crystals, can be purified or, dried in the centrifuge according to the invention, that is without washing. 1

I find by experience that different raw sugars require different high centrifugal forces to obtain the results desired. In some cases the centrifugal force may be as high as 7,000 times the weight of the mass or more.

No Drawing. Application filed February 11, 1927, Serial No. 167,598, and in Germany September 9, 1926.

I The centrifuges need not differ from those of ordinary construction except as regards the strength necessary to Withstand the relatively high centrifugal stresses.

IVhat I claim is .1. The process of refining sugar, which comprises applying to sugar with adhering mother liquor a centrifugal force suflicient to overcome thesurface adherence of the mother liquor and the crystals in the absenceof a washing agent.

2. The process of separating sugar crystals from adhering mother liquor, which comprises centrifuging such crystals and mother liquor at centrifugal forces in excess of 800 times the weight of the charge in the centrifugal to overcome-the surface adherence of the mother liquor and the crystals.

3. The process of purifying sugar crystals obtained from sugar manufacture by freeing them from their mother liquor-which comprises centrifuging the crystals'at a speed to develop a centrifugal force on the materials in excess of about 800 times the weight of the materials to drive the said liquor almost, en-

tirely from the crystals and to produce highsignature.

- JULIEN ERGE. 

